10 replies to this topic

[JDM]

Hi people.
So here's the issue I seem to be facing.
I made this huge monolithic stone, which will be ascending in a live action environment.
Everything working fine so far, Long shots look the way I want them to for this project.
the problem starts rising once I go for close ups (there are a couple of these shots).
As you will see on the video I added the displacement seems to just change from frame to frame. And it's not swimming textures, it literally looks like the stone is growing some new shapes while it turns around.
What could be the reason for that ?
I also added the houdini file, and textures as well here, but for file size reasons changed the textures from the 3500x3500 RAT files to 1750x1750 JPG.

First I thought it was a displacement bound issue, but I already upped that to 3 times the Displacement scale.
I upped pixel samples to 8/8 as well, but apart from render times going up there is no real difference.
Any ideas what this could be ?

thanks.

Attached Files

•  movingDisp.mov   2.48MB   166 downloads
•  movingDisp.zip   5.01MB   39 downloads

[Erik_JE]

MP or PBR ? If MP increase the shading quality of the object and it should fix it.

[JDM]

Erik_JE, on 18 July 2012 - 02:48 AM, said:

MP or PBR ? If MP increase the shading quality of the object and it should fix it.

Physical Based Rendering, I was told it was the better choice for this type of project.

[Matt_K]

Hiya,
You can try full pre-dicing the geo.
We had a similar issue that was solved this way after a few days of trying everything!

Hope that helps,
Matt.

[JDM]

Matt_K, on 18 July 2012 - 04:05 AM, said:

Hiya,
You can try full pre-dicing the geo.
We had a similar issue that was solved this way after a few days of trying everything!

Hope that helps,
Matt.

Thanks, but it doesn't seem to be doing the trick for me.
I turned on the Full predicing on the Geo node,and upped the shading and ray shading quality in mantra.
But it still seems to be the same for me.

[Matt_K]

Hey JDM,
Pity that wasn't the issue as it's a simple fix - will take a look at your file as soon as I get a chance.

Later,
Matt.

[DanBode]

Try increasing your displacement bounds.

[JDM]

Matt_K, on 18 July 2012 - 07:18 AM, said:

will take a look at your file as soon as I get a chance.

cheers

DanBode, on 18 July 2012 - 09:07 AM, said:

Try increasing your displacement bounds.

I already went as far as triple the value of the bounds (if I'm not mistaking, it normally is the same value as the displacement scale).
Would any value higher then that be helpful ?

[eetu]

Looking at your .mov, it looks to my eye as if the problems were at a certain distance plane from the camera.
That would indicate that it might be a problem with displacement texture mipmapping/filtering. I would check the filter type and size options for your displacement map, as well as any rendering parameters that look relevant.

[JDM]

eetu, on 18 July 2012 - 11:44 AM, said:

Looking at your .mov, it looks to my eye as if the problems were at a certain distance plane from the camera.
That would indicate that it might be a problem with displacement texture mipmapping/filtering. I would check the filter type and size options for your displacement map, as well as any rendering parameters that look relevant.

Thanks Eetu,
I have tried what you said, but without any real observable difference I fear.
There is always the chance I have skipped an important setting though, but I wouldn't know which one.

[ryew]

I would suggest swapping out your current displacement map for a simpler/cleaner one (or even a bump map instead of displacement) to determine whether the problem is being caused by your shader or your render settings before making excessive changes to your current settings.